Sanger J M, Reingold A M, Sanger J W
Cell Tissue Res. 1984;237(3):409-17. doi: 10.1007/BF00228425.
PtK2 cells were studied with scanning electron microscopy to record changes on the cell surface during mitosis and cytokinesis. During prophase, prometaphase and metaphase, the cells remain very flat with few microvilli on their surfaces. In anaphase cells, there is a marked increase in the number of microvilli, most of which are clumped over the separating chromosomes and polar regions of the mitotic spindle leaving the surface of the interzonal spindle region relatively smooth. Microvilli appear over the interzonal spindle region in telophase and the cells also increase in height. At the beginning of cleavage, the distribution of microvilli is roughly uniform over the surface but it becomes asymmetric at the completion of cleavage when the daughter cells begin to spread. At this time most microvilli are over the daughter nuclei and the surfaces that border the former cleavage furrow. The regions of the daughter cells distal to the furrow are the first to spread and their surfaces have very few microvilli. When chromosome movement is inhibited by either Nocodazole or Taxol, microvilli formation is inhibited on the arrested cells. Nevertheless cell rounding still takes place in the normal time period. It is concluded from these observations that the signal for the onset of chromosome movement in anaphase is accompanied by a signal for the formation of microvilli. It is suggested that there is also a separate signal for the cell-rounding event in mitosis and that microvilli do not play a role in this contractile process.
利用扫描电子显微镜对PtK2细胞进行研究，以记录有丝分裂和胞质分裂过程中细胞表面的变化。在前期、前中期和中期，细胞保持非常扁平的状态，表面微绒毛很少。在后期细胞中，微绒毛数量显著增加，其中大部分聚集在分离的染色体和有丝分裂纺锤体的极区，使得中间纺锤体区域的表面相对光滑。微绒毛在末期出现在中间纺锤体区域，细胞高度也增加。在分裂开始时，微绒毛在表面的分布大致均匀，但在分裂完成时，当子细胞开始铺展时，分布变得不对称。此时，大多数微绒毛位于子细胞核和与先前分裂沟相邻的表面。子细胞中远离分裂沟的区域首先铺展，其表面微绒毛很少。当用诺考达唑或紫杉醇抑制染色体运动时，停滞细胞上的微绒毛形成受到抑制。然而，细胞仍然在正常时间段内变圆。从这些观察结果得出结论，后期染色体运动开始的信号伴随着微绒毛形成的信号。有人提出，在有丝分裂中细胞变圆事件也有一个独立的信号，并且微绒毛在这个收缩过程中不起作用。
